Digestion products of human stabilized fibrin with various proteases are useful as diagnostic markers in clinical diagnosis. For example, a D-dimer produced by digesting human stabilized fibrin with plasmin (hereinafter sometimes referred to as "p-D-dimer") and a DD/E complex produced by digesting human stabilized fibrin with plasmin (hereinafter sometimes referred to as "p-DD/E complex") are widely used as a diagnostic marker of disseminated intravascular coagulation (DIC). In determination of the p-D-dimer and p-DD/E complex in a sample from a living body, agglutination of latex sensitized with a monoclonal antibody specific to the p-D-dimer is generally used.
Further, the e-D-dimer and e-DD/E complex of human stabilized fibrin are useful as a marker to predict postoperative disorder of multiple organs and pulmonary emphysema. Agglutination reaction of latex sensitized with the above monoclonal antibody specific to the p-D-dimer makes it possible to determine the p-D-dimer and p-DD/E complex produced by the action of plasmin, but does not make it possible to determine the e-D-dimer and e-DD/E complex produced by the action of granulocyte elastase. Therefore, there have been some attempts to determine the e-D-dimer and e-DD/E complex of human stabilized fibrin.
A monoclonal antibody which reacts with an N-terminal site (A.alpha.22-36) newly formed on the Aa chain of fibrinogen when it is digested with granulocyte elastase was reported (Blood Coagulation and Fibrinolysis, vol. 6, p 259, 1995). The monoclonal antibody has an antigen-binding site in an E domain, and therefore, different from the monoclonal antibody according to the present invention. Further, the former monoclonal antibody slightly reacts with fibrinogen, and thus, digestion products of fibrinogen or fibrin with granulocyte elastase in plasma cannot be determined by EIA wherein the former monoclonal antibody is used.
Further, polyclonal antibodies prepared by adsorbing and removing antibodies which can react with plasmin-digested D-monomer, plasmin-digested D-dimer, plasmin-digested DD/E complex and fibrinogen from polyclonal antibodies obtained by immunization with granulocyte elastase-D-fragment of fibrinogen (J. Lab. Clin. Med. vol. 102, p 858, 1983) are sometimes used, but the procedure is cumbersome.